Unitary eikonal formalism for multiproduction at high energy

Abstract

Unitary models for meson production in high energy nucleon-nucleon collisions are discussed in the approximation that all transverse momenta are small and that the centre-of-mass energy carried off by the produced secondaries is also small compared to the incoming nucleon momenta. Spin and isospin effects are neglected. It is shown that if the number of modes in which the mesons are produced is finite and if the requirement of crossing symmetry in the meson variables is properly taken into account, then it is possible to derive a general closed explicit expression for the S-matrix elements for all models of this kind.